【英文标准名称】:Informationtechnology-Multimediacontentdescriptioninterface-Part2:Descriptiondefinitionlanguage
【原文标准名称】:信息技术.多媒体内容描述界面.第2部分:描述定义语言
【标准号】:ISO/IEC15938-2-2002
【标准状态】:现行
【国别】:国际
【发布日期】:2002-04
【实施或试行日期】:
【发布单位】:国际标准化组织(IX-ISO)
【起草单位】:ISO/IECJTC1
【标准类型】:()
【标准水平】:()
【中文主题词】:信息技术;信息交换;数据表示;数据处理;界面;描述;定义;数据编码;程序设计语言;多媒体
【英文主题词】:Dataenciphering;Dataprocessing;Datarepresentation;Definitions;Descriptions;Informationinterchange;Informationtechnology;Interfaces;Multimedia;Programminglanguages
【摘要】:1ScopeofthisInternationalStandardThisInternationalStandardspecifiesametadatasystemfordescribingmultimediacontent.ItspecifiestheDescriptionDefinitionLanguage(DDL)thatcomprisespart2ofthestandard(ISO/IEC15938-2).ThegoalofthispartoftheMPEG-7InternationalStandardistospecifyalanguagethatwillenableMPEG-7usersanddevelopersto:·createvalidMPEG-7descriptionschemesanddescriptors;·developtoolssuchaseditorsandparsersforprocessingdescriptions,descriptionschemesanddescriptors;·generaterefinements,extensionsandmodificationstotheDDL.ThisInternationalStandarddescribesthefeaturesoftheDDL.ItdefinesthesyntaxoftheDDLconstructsanddatatypesandprovidesoptional(informative)examplesthatillustratetheapplicationoftheDDLtothespecificationandinstantiationofMPEG-7descriptions.2OverviewofDescriptionDefinitionLanguageThisInternationalStandard,knownasthe"MultimediaContentDescriptionInterface",aimsatprovidingstandardizedcoretechnologiesallowingthedescriptionofaudiovisualdatacontentinmultimediaenvironments.Thisisachallengingtaskgiventhebroadspectrumofrequirementsandtargetedmultimediaapplications,andthebroadnumberofaudiovisualfeaturesofimportanceinsuchacontext.Inordertoachievethisbroadgoal,thestandardspecifies:-Descriptors(D):representationsofFeatures,thatdefinethesyntaxandthesemanticsofeachfeaturerepresentation;-DescriptionSchemes(DS),thatspecifythestructureandsemanticsoftherelationshipsbetweentheircomponents,whichmaybebothDsandDSs;-ADescriptionDefinitionLanguage(DDL),toallowthecreationofnewDSsand,possibly,DsandtoallowtheextensionandmodificationofexistingDSs;-Systemtools,tosupportmultiplexingofdescription,synchronizationissues,transmissionmechanisms,fileformat,etc.TheDDLformsacorepartoftheMPEG-7standard.ItprovidesthesoliddescriptivefoundationthroughwhichuserscancreatetheirownDescriptionSchemesandDescriptors.TheDDLdefinesthesyntacticrulestoexpressandcombineDescriptionSchemesandDescriptors.AccordingtothedefinitionintheMPEG-7RequirementsDocument[1]theDDLis'...alanguagethatallowsthecreationofnewDescriptionSchemesand,possibly,Descriptors.ItalsoallowstheextensionandmodificationofexistingDescriptionSchemes.'TheDDLisnotamodellinglanguagesuchasUnifiedModellingLanguage(UML)butaschemalanguagetorepresenttheresultsofmodellingaudiovisualdata,i.e.,DSsandDs.TheDDLmustsatisfytheMPEG-7DDLrequirements.Ithastobeabletoexpressspatial,temporal,structural,andconceptualrelationshipsbetweentheelementsofaDS,andbetweenDSs.Itmustprovidearichmodelforlinksandreferencesbetweenoneormoredescriptionsandthedatathatitdescribes.Inaddition,itmustbeplatformandapplicationindependentandhuman-andmachine-readable.(Non-normative)DDLParserapplicationswillberequiredwhicharecapableofvalidatingdescriptionschemes(contentandstructure)anddescriptordatatypes[bothprimitive(integer,text,date,time)andcomposite(histograms,enumeratedtypes)],againsttheDDL.TheDDLParsersmustalsobecapableofvalidatingMPEG-7descriptionsorinstantiations,againsttheircorrespondingvalidatedMPEG-7schemas(DSsandDs).TheDDLdesignhasbeeninformedbynumerousproposalsandinputdocumentssubmittedtoMPEG-7sincetheMPEG-7CallforProposalsinOctober1998[2].IthasalsobeenheavilyinfluencedbyW3C'sXMLSchemaLanguage[3,4,5]andtheResourceDescriptionFramework(RDF)[6].Atthe51MPEGmeetinginNoordwijkerhoutinMarch2000,itwasdecidedtoadoptXMLSchemaLanguage[3,4,5]astheMPEG-7DDL.HoweverbecauseXMLSchemalanguagewasnotdesignedspecificallyforaudiovisualcontent,certainextensionshav
【中国标准分类号】:L81
【国际标准分类号】:35_040
【页数】:37P;A4
【正文语种】:英语


【英文标准名称】:Stateofrailwayvehicles-Passengerarea-Part4:Entrancedoors-Typeofconstruction:Slidingdoors
【原文标准名称】:铁路车辆的状况.乘客区.第4部分:上车门.结构类型:推拉门
【标准号】:DIN27203-4-2012
【标准状态】:现行
【国别】:德国
【发布日期】:2012-03-01
【实施或试行日期】:2012-03-01
【发布单位】:德国标准化学会(DE-DIN)
【起草单位】:
【标准类型】:()
【标准水平】:()
【中文主题词】:
【英文主题词】:Closingandcheckmechanisms;Coaches;Doors;Entrancedoors;Interlocks;Latches;Lockingdevices;Maintenance;Operationalsafety;Passengercompartments;Performancetests;Railwayapplications;Railwayvehicles;Railways;Repair;Safety;Slidingdoors;Testing;Tractionvehicles;Tramwaysystems;Types;Wagons;Workingplaces
【摘要】:
【中国标准分类号】:S51
【国际标准分类号】:45_060_20
【页数】:19P;A4
【正文语种】:德语